dr joe cincottaYou’ve probably heard people talk about sulfates, and seen “sulfate-free” called out on shampoo and cosmetic labels. Did you ever wonder... what IS sulfate? And why is having a product labeled sulfate-free or SLS free such a big deal?

With the help of Dr. Joe (Cincotta), an award-winning product developer and our in-house WOW wizard of formulation, we’re breaking down everything you need to know about sulfate, including the ever infamous sodium lauryl sulfate and sodium laureth sulfate (SLS).


“Sulfates, including sodium lauryl sulfate, are synthetic detergents, originally developed for the laundry industry,” Dr. Joe says.

Yes. Really. The sulfates that are found in so many shampoos were actually developed to wash your clothes. If you check the ingredient list on almost any commercial detergent, the first ingredient will be sulfate - likely sodium lauryl sulfate or sodium laureth sulfate.

So how did they end up in shampoos? What do sulfates do in shampoo?

Back in the day, before chemists created sulfates, the earliest forms of soap were made of naturally derived lye and lard. These soaps had very high pH (alkalinity), and while they were good for household chores (dishes, bedclothes, washing garments), they were aggressively harsh on hair and skin.

traditional lard soap

Then, in the 1940’s, scientists synthesized the first cleansers based on a chemical called sodium lauryl sulfate. This “sulfate” led to the first man-made detergent, and it was quickly adopted and used in a wide variety of household cleaning products.

From there the sulfate craze blew up! Sodium lauryl sulfate and sodium laureth sulfate were basically in everything - including shampoos and personal care products.


Three very good reasons.

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1) They were cheap and easy to produce.

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2) They were less damaging to hair and skin than lye or lard-based soaps.

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3) They lathered like crazy, which gave people a sensation of “powerful, super cleansing” when the lather rinsed off.

A whole new generation of super-charged, sulfate-based shampoos took over the hair care industry.

But sulfates were not all good news (as we know now). Great at cleaning (most!) fabrics and objects, sulfates are, unfortunately, a harsh way to clean your hair.


Why are sulfates bad for hair? Because sulfates are harsh chemical compounds with a high-charge density, their impact on each hair strand is two-fold.

1. They strip away natural oils

Sulfates like sodium lauryl sulfate and sodium laureth sulfate don’t just lift away dirt and grime. They also strip away the delicate layers of natural moisturizers (created by your body’s own sebum) that protect, smooth and keep your hair and skin optimally healthy.

sodium laureth sulfate and sodium lauryl sulfate magnifying glass

2. They make your hair strands swell up and cause the outer cuticle layer to open

This is due to sulfates’ high-charge density. Once the cuticle is open, it’s much more difficult to keep anything critical inside, like the natural moisturizers and proteins that keep your hair hydrated and strong.

healthy vs unhealthy hair cuticle

This is an issue for everyone, but can be especially problematic for people with dehydrated or compromised hair (like those with naturally curly texture, color-treated or chemically-processed hair), as these types are already damaged, weak, porous, rough and dull.


Yes, sulfates also cause hair color to fade. When the cuticle layer is lifted due to swelling, color molecules leach out just like natural moisturizers.

In fact, according to Dr. Joe, “Eighty percent of color fade happens because of wash-out from sulfate-based shampoos that contain ingredients like sodium lauryl sulfate and sodium laureth sulfate.”

The bottom line? If you value your hair’s health and hair color, make sure your shampoo does not contain sulfates. Instead, look for a formula that’s SLS free.


So if sulfates are a deal breaker… what’s the best shampoo for your hair?

“Definitely look for a shampoo that is sulfate-free (otherwise known as SLS-free). But beware,” Dr. Joe warns, “not all sulfate-free formulas are the same! Some shampoos are “sul-FAKE-free!”

It’s true! Just because a shampoo is labeled sulfate-free doesn’t mean it has your hair’s best health in mind. Let’s dive into it!


What does sulfate free mean? Unlike sulfates, gentler sulfate-free cleansing agents are intended to have a low-charge density to help minimize or eliminate hair swelling while sudsing. Without swelling, your cuticle remains smooth and closed, keeping all vital moisture, proteins and color locked inside.

The key word here being “intended.” Because like we said, not all sulfate-free formulas are created equal. In fact, there are two main ways sulfate-free shampoos actual fail to protect to health of your hair:

1. Many sulfate-free shampoos are formulated with cheaper sulfate-free cleansing agents

High quality sulfate-free cleansers can get pretty expensive. So in order to lower costs, cheaper alternatives are often used.

These shampoos, while labeled “sulfate-free,” contain ingredients like “sodium C14-16 olefin sulfate” or “sodium xylene sulfonate” that, while not chemically classified as “sulfates,” have properties (like a high-charge density) that exactly mimic harsh, aggressive sulfate behavior. Aka, they swell the hair strand, which results in moisture and protein loss, plus color fade.

2. They try to cleanse AND solve your hair problems

You’re probably familiar with thickening / defrizzing / hydrating, etc. shampoos. Most shampoos today try to multitask while you suds (including sulfate-free shampoos).

While this might sound ideal, the truth is these formulas contain added ingredients that are designed to stay behind on your hair and scalp in order to deliver on their benefits. Overtime, this can result in buildup that never washes out, leading to scalp issues, blocked follicles and hair thinning.


How to check if shampoo is sulfate free? If you’re wondering what ingredients you need to be on the lookout for when it comes to shopping sulfate-free shampoos, we got you covered!

A sulfate free shampoo means you want these ingredients…

  • Sodium Cocoyl Glycinate
  • Sodium Cocoyl Isethionate
  • Sodium Methyl Cocoyl Taurate

Types of sulfates in shampoo you don’t want…

  • Sodium Lauryl Sulfate
  • Sodium Laureth Sulfate
  • Ammonium Laureth Sulfate
  • Ammonium Lauryl Sulfate

Other ingredients to avoid…

  • Silicones
  • Conditioning, thickening or anti-frizz ingredients
  • Oils

For more information on hair care ingredients to avoid, check out our ultimate ingredients guide.


We know, that’s a lot of info to digest! And the thought of trying to find a shampoo that checks off all these boxes might seem overwhelming…

Luckily, our team has been making shampoos for over 40 years. So when developing our current formulas, our Color Wow Lab took special care to keep your hair’s best interests in mind.

color wow only good for you ingredients

Color Wow Color Security Shampoo and Curl Wow Hooked Shampoo are made with a proprietary sulfate-free base that’s ideal for all hair types, even the most fragile and chemically-damaged.

For all hair types – Color Security Shampoo

For curly and coily hair – Hooked Shampoo with Root Locking Technology

color wow color security shampoo

  • High-quality sulfate-free cleansing base

We formulated using only low-charge density sulfate-free cleansers that won’t swell your hair strands or open the cuticle.

  • Ultra gentle + non-stripping

Made with a special Japanese amino acid-based cleansing agent called Sodium Cocoyl Glycinate (often found in face washes), our shampoo cleanses thoroughly without stripping away your hair’s natural oils. This cleansing agent is also high-foaming and delivers a luxurious, rich lather not often found in sulfate-free formulas.

  • 100% clean, residue-free

Our formula contains NO silicones, conditioning, thickening, anti-frizz or any ingredient that results in buildup. Every ingredient rinses completely off for your healthiest, cleanest hair and scalp.

  • Color-safe

Thanks to our non-swelling sulfate-free cleansers that keep your color from leaching out, our formula is clinically-proven to prevent color fade for at least 20 washes.

  • Anti-thinning Root Locking Technology (in Hooked Shampoo only)

Our Curl Wow Hooked Shampoo is specially formulated with root-strengthening Procapil® to help reduce shedding and breakage. This is especially ideal for fragile or textured hair that’s frequently pulled tight, braided, and weaved.


Sulfates are harsh chemical surfactants that dry out hair and can strip away color. The best piece of advice from Dr. Joe: “When it comes to shampoo, take away the sulfates. And if you want the cleanest, healthiest hair and scalp, take away any ingredients that have nothing to do with cleansing.”

For more advice from Dr Joe on all things ingredients, take a look at his guide to alcohol and hair care and learn the 4 ways to check if your hair is healthy.

Dr. Cincotta holds a Ph.D. in Organic Chemistry from the City University of New York, and is currently VP of Research + Development at Color Wow.

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